Effect of Laser Surface Melting on Microstructure of Cold Sprayed Ni20Cr Coatings

In this study, Ni20Cr coatings were obtained by cold spraying on an aluminum alloy 7075 substrate. The obtained coatings were characterized by a uniform microstructure and low porosity. The sprayed coating has the same phase composition as the powder used. Next, the cold sprayed coatings were heat treated using a TRUMPF TLF 6000 TURBO (4 kW) CO2 laser. The laser surface melting of the coatings resulted in the formation of a columnar structure and an improvement in their mechanical properties. The Ni20Cr cold sprayed coatings after additional laser melting showed lower porosity and an increase in microhardness and Young`s modulus.